1. Field of the Invention
The present invention relates to a liquid crystal display device.
2. Description of the Related Art
A liquid crystal display panel includes an array substrate having a display region and a frame region. A plurality of pixel circuits are disposed on the display region. The frame region located around the display region. A plurality of thin film transistors are formed on the array substrate. At least a part of a semiconductor film formed on the array substrate forms a channel of each thin film transistor, and the fact is known that light from a backlight enters the semiconductor film and produces a leakage current. In order to prevent this leakage current, a light blocking film may be provided under a gate electrode. The light blocking film is disposed to prevent light from the backlight from entering the semiconductor film.
JP2011-238835A discloses a thin film transistor in which a light blocking film is provided under a gate electrode, and an insulating film is provided between the gate electrode and the light blocking film, and a liquid crystal display device using the thin film transistor.
In order to miniaturize a liquid crystal display device while securing a display region, it is necessary to narrow a frame region around the display region. In addition, in recent years, a gate line driving circuit including many thin film transistors has been formed in the frame region. If the frame region is to be narrowed, it is necessary to miniaturize the gate line driving circuit. On the other hand, there are cases where, when the light blocking film is provided, a reaction of the thin film transistor to a signal applied to the gate electrode gets worse.